Woom 3 Seat Post Adapter - stainless steel The new woom seat posts currently offered measure around 23mm in diameter whereas the older models are larger and measure 25.4mm and to my knowledge are no longer available to purchase. These stainless steel sleeves get slotted inside the frame of the older model bikes and reduce the diameter to fit the new thinner post while still utilising the quick release clamp. This adapter may well fit other models, only have a woom 3 to take measurements off, please drop me a message if you need any more information.
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